A type of unmanned aerial vehicles (UAVs) known as drones are the subject of increased scientific research as their use increases and becomes more diverse. Recent news stories have featured drones being used to transport medical supplies in Africa, deployed by police to crime scenes, and in a halftime light show at Super Bowl LIII.
UAVs belong to a class of flying machines called rotorcraft that also includes helicopters. They lift into the air using rotor blades revolving around a mast. Unique features of rotorcrafts, explained University of New Mexico Associate Professor of Mechanical Engineering Dr. Svetlana Poroseva, are the ability to take off and land vertically, and hover in the air. This makes them effective for use in residential areas and in agriculture for sowing, spraying, irrigating, and monitoring crops.
“This is an active research area, with the focus of our research group being on the aerodynamic efficiency of drones and small rotorcrafts,” Poroseva noted. Recently, a paper Computational Study of Small Rotor at Hover Using CFD and UVLM was published by Poroseva in collaboration with her colleagues Ph.D. student Andrés Pérez and Associate Professor of Mechanical Engineering Omar Lopez from the Universidad de los Andes in Bogotá, Colombia, and industry partner Jaime Escobar from the Colombian company Advector Unmanned Systems. Student support was also provided by Departamento Administrativo de Ciencia, Tecnología e Innovación de Colombia.
The paper compares accuracy and affordability of two different computational methods to simulate small rotors in hover flight. Testing and comparing preliminary rotor designs in simulations before their production is an important and necessary step in a quest for better drones and other rotorcraft, she explained, but this process can be very expensive.
The methods compared were Computational Fluid Dynamics (CFD) simulations using commercial software, and the unsteady vortex lattice method (UVLM). Because of the complex calculations and the amount of data generated by their simulations, Poroseva and her colleagues used various resources, including the systems at the UNM Center for Advanced Research Computing (CARC).
“Overall, UVLM with the proposed viscous correction produces results close to those from CFD simulations and experiments. Thus, this method is a suitable tool to study aerodynamics of small rotors. Moreover, the computational cost of UVLM is much less than that of CFD simulations, making this approach affordable alternative to CFD,” the research concludes.
Dr. Poroseva said that availability of CARC resources free of charge for UNM students and faculty was a significant factor that helped in making this international project possible.
“Andrés [Pérez] had an internship here at UNM with me for a year and was supported by the Universidad de los Andes in Bogotá. We are looking to continue our collaboration in the future and have more students who would like to come here,” Dr. Poroseva said. “CARC resources are unique. Many of my colleagues in U.S. are really envious of our facilities. In my field of research, CARC is considered one of the best. Colleagues want to come and cooperate with us.”